Step.



No. 771,772.A n PATENTED OCT. 4, 1904.

' M. V. B. ETHRIDGE.

STEP.

APPLICATION FILED DB0. 5, 1903.

N0 MODEL UNITED STATES Patented October 4, 1904.

PATENT OEEICE.

MARTIN V. B. ETHRIDGE, OF NEI/V YORK, N. Y., ASSIGNOR, BY MESNEASSIGNMENTS, TO EMPIRE SAFETY TREAD COMPANY, OF BROOKLYN, NEV YORK, ACORPORATION OF THE DISTRICT OF COLUMBIA.

STEP.

SPECIFICATION fori'ning part of Letters Patent No. 771,772, datedOctober 4, 1904. Application filed December 5, 1903. Serial No. 183,854.(No model.)

To all whom, it may concern:

Be it known that I, MARTIN V. B. ETHRIDGE,

a citizen of the United States, and a resident of New York city, in thecounty and State of New York, have invented a new and useful'Improvement in Steps, of which the following is a specification. y

This invention relates to safety-tread steps for use on car-steps orstairways where Vthe IO trafHc is very heavy and where there is greatwear and extra danger of slipping.

It has for its object to provide a step the tread of which is composedof non-slipping rough artificial stone, such as carborundum, made in vI5 small sections and heldin a metal bed-plate or foundation, the saidartiiicial stone being much harder than the clamping portion of thebedplate which holds it in place in order that the said clamping portionwill wearV away in 2O advance of the non-slipping stone tread, leavingthe latter always projecting and exposed to Contact. To accomplish thisresult, I make wearing-strips of porous artiiicial stone, such ascorundum or bicarborundum, which is made excessively hard andsuiiiciently rough to prevent slipping. The stone so made is iirst puttogether with a binding substance which renders it proof against theweather. Thus rain or other moisture and changesof temperature have nodeteriorating effect upon the stone.

In the accompanying drawings, which form a part of this speciiication,my invention is fullyillustrated, with similar letters of referlence toindicate corresponding parts, as folows:

Figure l represents a top view showing a section of acompletedstep-tread. Fig. 2 represents a longitudinal sectional View on the 4oline 2 2, Fig. l. Fig. 3 represents atop View of one of the carborundumstrips. Fig. l

represents a top view showing a section of a completed step-tread withstay-wires introduced to bind and strengthen the structure. 4 5 Fig. 5represents a side elevation of the same, showing in section the finishededge with the surrounding metal, likewise the edge of the carborundumstone with the wires in place before the surrounding metal is applied.Fig.

6 illustrates a plan view showing a section of 50 the carborundum stonesand wiresas they are united before the surrounding metal is applied.Fig. 7 represents an end elevation showing the location of thecarborundum strips within the surrounding metal, likewise 5 5 the endsof the carborundum strips without the surrounding metal, illustratingthe manner in which the transverse wire is curved between thecarborundum stone strips.

Referring to Figs. 2 and 3, a designates the 6o carborundum strip, whichis provided with depressions a', running transversely of its surface atsuitable intervals in order that the metal which surrounds the stonesand holds them in place may be properly united between the strips, asshown at a2, Fig. 1. The process of making this particular step wherethe transverse wires are not used is to place the stone strips a withinthe iron mold at suitable intervals, leaving suiiicient space be- 7otween them for a fluid metal to fiow freely.

A metal softer than the stone, which will contract in cooling, is thenmixed and when sufficiently melted is poured within the mold around thecarborundum stone strips, the same being held within the mold until themetal is cool, the result being that the contracting of the metal duringthe process of cooling shrinks itself so firmly around the carborundumstrips after having penetrated 8O its pores while hot that the stripsbecome perfectly solid and fixed'within the metal without a possibilityof their becoming broken or detached by any amount of wear or use. Inorder, however, to reinforce the above-described structure and make itstiffer and less liable to bend where the trafiic is excessively heavy,I employ the binding-wires c and c, which may be woven together orplaced with the transverse wires c on top of the longitudinal wires c',as illustrated.

The carborundum strips a' in the last-described construction are madeprecisely the same as those above described', although it is notnecessary to have them in one continuous strip. They could be made inshort pieces, with the transverse wires c running between their ends,leaving each individual blo'ck of stone to be entirely surrounded bymetal, with a stay-wire passing along its sides and across its ends.

When I use the last-named method of construction, I usually have thetransverse depressions a in the carborundum strips on the lower side ofthe stone, so that the metal which forms the bed-plate c2, Fig. 5,covers the entire opening and leaves the carborundum strips a, Fig. 5,projecting slightly above the surrounding metal e, in which case theupper surface of the tread-step when finished will show, as illustratedin Fig. 4, with alternate strips of stone and metal. The process ofcombining the parts in this last-described method of construction ispreciselythe same as that previously described. The wires andcarborundum strips are held in place within a suitable mold, and thecontracting hot metal is poured within the mold and cast in the desiredform, and

the stay-wires being composed of tin and properly prepared the moltenmetal will solder itself fast to the wires and contract around thestone, as heretofore described, thus making a very strong andpractically indestructible step. I would state, however, that thisessential is necessary to the success of the invention, that thecarborundum strips or pieces be embedded in and surrounded by a metalsofter than the strips, which will receive and absorb the blow withoutpermitting a possible movement of the carborundum stone. Soft metal,such as lead, might be used, or an alloy of lead and antimony might alsobe employed; but the invention is not limited to any precise metal ormetallic alloy of the character mentioned. Hence the blows received bythe strips ce are transmitted to and absorbed by the metal surroundingthe same, the metal serving as a bed and holding the strips absolutelysolid and rigid in position.

Having thus described my invent-ion, what' .carborundum or other hardartilieial-stone pieces surrounded by a metal softer than the stonepieces, said metal holding the said pieces in position, and forming thefoundation or basis of the said step, and intermediate wires running intwo directions within the said metal and forming suitable meshes, withinwhich the said carborundum stone rests, the whole being molded togethersubstantially as described.

4. In a non-slipping tread-step, a series of carborundum or hardartificial-stone strips provided with suitable transverse depressions,stay-wires seated in said depressions, and a metal bed softer than saidstrips contracted upon the same and in which said strips are seated.

5. A non-slipping tread-step composed of carborundum or other hardartificial-stone pieces, longitudinal and transverse wires surroundingsaid pieces, and a metal softer than the stone pieces shrunk upon thelatter and -said wires.

In testimony that I claim the foregoing specification I have hereuntoset my hand this 17th day of November, 1903.

MARTIN V. B. ETHRIDGE.

In presence of- E. A. PEEBLES, J. W. SCOTT.

